World must switch to plant-based diets to halt biodiversity crisis, say experts

Global food production threatens 24,000 species, warn UN and Chatham House policy advisers

About 40 per cent of world grain harvests are fed to farmed animals, it’s estimated (AFP via Getty Images)

Cheap worldwide food production is the main cause of accelerating loss of nature, some of the world’s leading policy advisers are warning.

Agriculture will further destroy ecosystems, driving the biodiversity crisis, unless we urgently make big changes to food systems, including shifting to more plant-heavy diets, the experts say.

And any further destruction of habitats and the living world will threaten our ability to sustain human populations, according to the report by independent think tank Chatham House, the United Nations Environment Programme (UNEP) and Compassion in World Farming (CiWF).

It says the effects of producing more food at lower cost is also a major driver of the climate crisis, accounting for around 30 per cent of total human-produced greenhouse gas emissions.

The experts have calculated that global food production threatens 24,000 of the 28,000 species currently at risk of extinction.  

With the sixth mass extinction under way, the rate of species loss now is higher than the average rate over the past 10 million years.  

The report authors call for urgent reform of food systems, suggesting three key actions: changing global dietary patterns, protecting and setting aside land for nature, and farming in a more nature-friendly and biodiversity-supporting way.  

They say the “cheaper food paradigm”, involving clearing land for agriculture, and further intensifying farming, leads to vicious circles of greater demand for food that must also be produced in the same damaging way.

It depends heavily on fertilisers, pesticides, energy and large quantities of water, and on unsustainable monoculture, which reduce the variety of landscapes and habitats, threatening or destroying the breeding, feeding and nesting of birds, mammals, insects and microbial organisms.  

As the report was launched, renowned anthropologist Jane Goodall warned that the drive for cheap food was also linked to the risk of further virus epidemics.

“The intensive farming of billions of animals globally seriously damages the environment, causing loss of biodiversity and producing massive greenhouse gas emissions that accelerate global warming,” she said.

“The inhumane crowded conditions not only cause intense suffering to sentient beings but enable the transfer of pathogens from animal to human, risking new zoonotic diseases.  

“On ethical grounds it should be phased out as soon as possible.”  

The report also links food production to “novel and dangerous” zoonotic diseases – those that jump from animals to humans – by allowing pathogens to move between wild and farmed animals.  

To grow crops to feed livestock for meat and dairy, large swathes of land are cleared, both in developed and developing countries. Up to 90 per cent of soya is used to feed meat animals, while livestock farming is a "key player" in water use, according to the World Economic Forum.

Ms Goodall said the world should value food, as she did as a child during the war, and waste less.  

Philip Lymbery, of CiWF, said the idea that intensive farming saves space was not true, since 40 per cent of world grain harvests were used to feed farmed animals.

What to do?

The report calls for three “interdependent” actions:

• Stopping converting land for agriculture is “the most effective way of preserving biodiversity”. 

“The setting aside of land for nature and the shift to nature-friendly farming depend on dietary change, and will become increasingly difficult to achieve if continued growth in food demand applies ever-growing pressure on land resources,” the report authors say.  

The experts say that as governments seek to “build back better”, global policymakers need to translate these actions into national targets.